* Are you doing drip or bath?
* How much nutrient solution are you using (how are you measuring your nutrients)?
* Is the plant indoors or outdoors?
* If Indoors, is their air moving around the plant?
* What temp is the plant in?

How much air bubbles do you have in your bath? It should look like the water is boiling. Measuring the solution by physical amount seldom gives you what you want, you may want to get a meter and check how many PPM your solution has. For peppers it should be around 500 PPM. Temperature or Temp is pretty important, it should never go above 90 if you can help it, and for high temps like 85+, a fan blowing on the plants helps a lot. Water, before you put water in you bath and mix your solution let it stand overnight to rid it of Chlorine. Check you PH, keep it between 5.8 and 6.3 for maximum growth and health.

It wouldn't hurt your plants at all to get a spray bottle filled with water and maybe half a tsp of dish soap. Spray the leaves once a day or so. Those spots look like some kind of critter attack. Even if it isn't, the mild soap solution will not hurt the plants, but it just might help. Don't forget the undersides of the leaves as well. chuck

By the way, adding a little bit of soap to water the way chuck describes is also a common method to improve the performance of foliar sprays. It's called a "surfactant" and the idea is to break the surface tension in the water so that it won't bead up on the leaves. Beads of water act like tiny magnifying glasses that focus light and burn the leaves.

Plus, if you can spread the water out more thinly and completely you get more water in contact with more leaf surface, and more absorption. You can make a DIY foliar spray by mixing a very weak nutrient solution with a tiny bit of soap and spraying your plants with it.

The key to successful foliar feeding is to do it in the very early morning (very near sunrise) or just before sunset. You want a little light so the plant has power for its metabolism, but not so much light that it can heat the water up and hurt the plant.